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of another system, especially a computer program designed for that purpose
CFD Projects
CAE Projects
Customized Software Tools
Automobile Head Lamp
Thermal Analysis
Conclusion
Since Lens and Housing are walls, the heat flux across them is an important indicator of the thermal situation. Conduction is not considered in these walls as they are not surrounded by fluid volume on both sides, and are governed by the outside temperature, and the internal solid mesh is not generated. Similarly Bezel is also modeled as zero-thickness internal wall. It was found that some spots are seen to show focused radiation fluxes much higher than neighbour regions. This could mean that the areas exposed to this high flux show a large rise in temperature. It was also found that the temperature level in some of the common parts of the head lamp was very high in both low beam and high beam conditions, which would lead to sagging and deformation. This could be due to many factors such as relative placement of high-beam and low-beam filaments, and the presence of shield in low beam case which could focus a region of heat around the screw, raising its temperature and the temperature of air around it.
Objective
The objective of the project was to conduct thermal analysis for VW Polo headlamp to point out the regions of high temperature and heat flux gathered during the course of normal operation and testing standards. The project consisted of numerical simulation of the headlamp geometry in order to study the temperature and heat flux fields over the entire domain. Based on this data it is possible to pinpoint the cause of undesired behaviour.. Performance is measured by a throw profile test wherein the light throw profile of the headlamp is tested over a period of time under varying environmantal conditions. Due to the environmental conditions as well as the heating caused by the lamp's filaments, the structural rigidity of the headlamp components was modified leading to a change in the light throwing profile. By doing a study of the thermal situation inside the lamp it can be understood as to what could be the cause and exact location of structural failure or sagging. The entire study was done for two different load cases termed "High beam" and "Low beam", due to the two different operating modes of the H4 bulb, respectively.
Modeling and Analysis:
3D model of the entire headlamp was created using modeling tool. Each component like Bezel, lens, reflectors, Housing and the common parts of the head lamp was studied and modeled. As radiation is the main cause of heating the heating from bulbs like H4, PY21W and W5W studied. The mesh generated for the headlamp assembly was hybrid structuredunstructured mesh of mainly triangular elements with some hexahedral elements. The entire fluid domain is a volume mesh (3D elements) and also the internal components have a 3D solid mesh inside them (reflectors, common parts). After the meshing various parts of the mesh are assigned patches and each patch is assigned appropriate boundary condition. Then the equations for air flow, conduction, convection and radiation are solved over the entire domain in an iterative fashion. The >governing equations provide the entire temperature field based on boundary conditions.